Long Parliament,session of the English Parliament summoned in November 1640 by King Charles I; it has been so named to distinguish it from the Short Parliament of April–May 1640. The duration of the Long Parliament has been held to have extended either until April 1653, when its remaining members were forcibly ejected by the Cromwellian army, or until March 1660, when its members, finally restored, passed an act for its dissolution. Legally the act of 1660 was as invalid as the ejection of 1653, because it lacked royal assent. An act of the Convention Parliament of April–December 1660 can be said to have finally dissolved the Long Parliament, though the Convention was itself not a lawful parliament because it had not been summoned by the king; its acts were reinforced by later legislation.

Charles I summoned both the Short and Long Parliaments in 1640 because only the Parliament could raise the money he needed to wage the second Bishops’ War against the Scots, who were resisting his attempts to impose episcopacy on them. Because of disputes he dismissed the Short Parliament hastily; the Scots then invaded northern England, and, in order to buy them off, a fresh recourse to Parliament was unavoidable. The Long Parliament proved much more intransigent than the Short, however. During its first nine months it brought down the king’s advisers, swept away the machinery of conciliar government developed by the Tudors and early Stuarts, made frequent sessions of Parliament a statutory necessity, and passed an act forbidding its own dissolution without its members’ consent. Tension between the king and Parliament steadily increased, notably upon Charles’ abortive attempt to arrest five of its members in January 1642, and the Civil War Wars broke out later that year. After the king was finally defeated in the field (1646), new members were elected to replace those who had joined the army exercised political power, and in December 1648 Colonel Thomas Pride expelled all but about 60 members of the Long Parliament (“Pride’s Purge”)king (the “recruiters”), but real power passed to the army. In December 1648 Col. Thomas Pride carried out what came to be known as “Pride’s Purge.” Acting on behalf of the generals, he secluded more than half of the 460 members of the Commons and several of the handful of peers still in attendance. Most of the remainder refused to take their seats (at least until long after the regicide) or to recognize the legitimacy of what the army had done at Pride’s Purge. The surviving group, known to historians as the Rump, brought Charles I to trial and execution in January 1649; it was forcibly ejected in 1653. After the Protectorate of Oliver Cromwell, the Rump was restored in May 1659 and expelled in October. It was reestablished in December 1659, and, after those excluded in 1648 had joined it, it dissolved itself; the newly elected Convention Parliament then opened negotiations for the restoration of Charles II.